From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757434Ab2DZPGb (ORCPT ); Thu, 26 Apr 2012 11:06:31 -0400 Received: from casper.infradead.org ([85.118.1.10]:53715 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751590Ab2DZPGa (ORCPT ); Thu, 26 Apr 2012 11:06:30 -0400 From: Arnaldo Carvalho de Melo To: Ingo Molnar Cc: linux-kernel@vger.kernel.org, Arnaldo Carvalho de Melo , David Ahern , Frederic Weisbecker , Mike Galbraith , Namhyung Kim , Paul Mackerras , Peter Zijlstra , Stephane Eranian Subject: [PATCH 1/4] perf annotate browser: Handle NULL jump targets Date: Thu, 26 Apr 2012 12:06:14 -0300 Message-Id: <1335452777-27326-2-git-send-email-acme@infradead.org> X-Mailer: git-send-email 1.7.9.2.358.g22243 In-Reply-To: <1335452777-27326-1-git-send-email-acme@infradead.org> References: <1335452777-27326-1-git-send-email-acme@infradead.org> X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Arnaldo Carvalho de Melo In annotate_browser__mark_jump_targets 702 dlt = browser->offsets[dl->ops.target]; 703 bdlt = disasm_line__browser(dlt); 704 bdlt->jump_target = true; 705 } 706 707 } (gdb) p size $5 = 2415 (gdb) p offset $6 = 140 (gdb) p dl->ops.target $7 = 143 (gdb) p browser->offsets[143] $8 = (struct disasm_line *) 0x0 (gdb) p dl->name $9 = 0x2363bd0 "je" (gdb) Really strange, the code assumed that at the jump target we would have an assembly line, but only in the previous instruction offset we have a 'lock': (gdb) p browser->offsets[144] $10 = (struct disasm_line *) 0x0 (gdb) p browser->offsets[142] $11 = (struct disasm_line *) 0x27bd620 (gdb) p browser->offsets[142]->name $12 = 0x237a8a0 "lock" (gdb) I'll study this more, but for now I'll just check if there is a disasm_line at dl->ops.target, i.e. a valid jump target. Reported-by: Hagen Paul Pfeifer Reported-by: Ingo Molnar Cc: David Ahern Cc: Frederic Weisbecker Cc: Mike Galbraith Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lkml.kernel.org/n/tip-inzjrzyqhkzyv78met2vula6@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/ui/browsers/annotate.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/tools/perf/ui/browsers/annotate.c b/tools/perf/ui/browsers/annotate.c index 9e3310c..4c83fe3 100644 --- a/tools/perf/ui/browsers/annotate.c +++ b/tools/perf/ui/browsers/annotate.c @@ -700,6 +700,13 @@ static void annotate_browser__mark_jump_targets(struct annotate_browser *browser } dlt = browser->offsets[dl->ops.target]; + /* + * FIXME: Oops, no jump target? Buggy disassembler? Or do we + * have to adjust to the previous offset? + */ + if (dlt == NULL) + continue; + bdlt = disasm_line__browser(dlt); bdlt->jump_target = true; } -- 1.7.9.2.358.g22243